Watch construction



Dec. 1, 1936. BULOVA 2,062,637

WATCH CONSTRUCTION Filed Aprii 15, 1936 ATTORNEY Patented Dec. 1, 1936 UNITED STATES PATENT OFFICE WATCH CONSTRUCTION Ard Bulova, New York, N. Y., assignor to Bulova Watch Company, Inc., New York, N. Y., a corporation of New York Application April 15, 1936, Serial No. 74,396

1 Claim. (01. 5890) It is known that the winding and setting stems small part, not merely for reason of appearance of watches, and more especially those of watches but also because the less the extent of the crown of small size, are subject to breakage. Among the more likely it is to escape knocks. The small watches the number of stems broken is stem is apt to be extremely slender.

large, which means that many owners are incon- In Fig. 1 the parts 2 and 3 represent the case, 5 venienced and put to expense. Moreover it is which is usually composed of a front and a back significant that a considerable number of stems part fitting one over the other. The part 4 is are broken in the casing of watches. a thin dust band which is interposed frictionally One cause of stem breakage is a blow or shock between the case and the periphery of the movereceived by the crown and transmitted directly ment 5, and which may overlie only the top of 10 t the St m, Busting of th te may als b the movement or may extend all the way around a predisposing cause. It appears that slight lack it. At the region of the winding stem 6 the dust of alinement between the part of the movement band has an opening larger than the stem, and into which the stem fits and a part of, or a part eXtehdiIig DWa f m this re on of the dust associated with, the case, which may bear against h d ou an Opening in the Case there iS 15 the stem above the movement, may put the stem a tube 8. This tube and dust band enter into the under a strain which 111 cause or c hduc to combination of the preferred form of execution breaking. Thus, means for protecti of th of the invention, but in certain instances, though movement nd st m f m d t d i tur with less advantage, one or both may be omitted.

much to be desired, or for supporting the, stem, The dust band and neck are intimately associ- 20 or both, may as the result of small inaccuracy ated With the ease and y be Considered as a give rise to such a condition of strain. Considerp Of the ease as distinguished f om the moveing the unavoidable fragility of many of the mentwinding stems, it is doubtless true that there are Screwed or otherwise made fast on the upp th r causes f st b k ge portion of the stem there is a crown post 9, which 25 It is an object of this invention to minimize is in floating relation to the crown onor materially reduce the breaking trouble with Versely, the Crown iS in floating ation to the winding stems, and to this end the invention compest but has driving C e t on therewith. The prises a simple construction, 11 adapted for construction illustrated in the drawing is adapplication to extremely small parts, in which ly adap fer the P D d onstitutes 30 the crown has a floating connection with a post a more Specific feature of the ventio hich i fast on th t In this construction the post 9 has a fiat head It is a further object, however, to combine ll composed of one or more u s 2| wh p j ct either a dust d i t proofing or a support laterally from the top of the post, and these lugs for the stem or crown, or all of these, with a py a Cavity l2 i the crown, Where one or 5 floating connection between the crown and stem, more internal lugs and e es l4 coact with to the end that th mov m t nd t may the lugs 2|, or their recesses, to provide a driving have a high degree of protection. engagement so that turning of the crown will The accompanying drawing il t t t preturn the stem for Winding and setting. It is to 40 ferred embodiment of the invention, but it will he notedthat there is Substantial Clearance 40 be understood that the embodiment may be vatween the formations 2| of the p 9 d t e ried. formations l3 inside the crown, so that there In the said drawing: can be movement in all directions laterally be- Figure 1 is a fragmentary section of a watch tween the post and the crown. Preferably, also,

taken in a plane substantially midway between there is sufficient head room in the cavity I2 to 4.5 the front and the back, the portion of the moveperm t f rela ive vertical or tilting movement.

merit being shown in elevation Without details, The pa j t es ib d are retained in loose and a small portion of the post being in elevation; enga e y a bushing W c is inserted d tightly into the crown from beneath, and under- Fig. 2 is a section taken on the line 22 of lies the projections 2| of the post 9. 50 Fig. 1. The construction of the crown, crown post and For clearness of illustration the views are on stem which has been described will, without other a greatly enlarged scale, and relative proportions provisions, relieve the stem of the severity of varineed not be taken to be accurate. In a small ous shocks to which it might otherwise be subwatch it is desirable that the crown be a very jected. 55

With the presence of the neck 8, however, better protection of the stem, as well as a high degree of dust and moisture proofness, may be realized. It will be observed that the neck 8 extends upward within an annular recess between the post 9 and the bushing I5 which forms virtually an integral part of the crown. Between the inside of the neck 8 and the outside of the post 8 there is a space or clearance I8 which is so designed as to be large enough to prevent strain being imposed on the stem 8 notwithstanding such degree of misalinement as may exist between the neck 8 and the portion of the movement in which the stem is engaged. This overcomes a difliculty which has been found to exist in dust-proofing constructions having a neck of this character. 0n the outside of the neck 8, however, between it and the cylindrical internal wall of the crown or bushing there is little or no material clearance. Preferably, indeed, the crown turns on the outside of the neck 8 as a journal bearing. Thus dust and moisture are quite effectively excluded from access to the stem and movement, and the neck 8 relieves the stem 6 of shocks against the crown, since because of the floating connection between the crown and the post 9 the force of a blow on the side of the crown will be taken by the neck 8 and not be communicated to the stem.

Even though the spacing between the neck 8 and the inside of the crown were larger, the circuitous course which would have to be followed by foreign matter before it could get in around the stem would be a material protection in that respect; and even though the play between the crown l0 and the post 9 should be taken up under shock before the crown bore laterally against the outside of the neck or the post bore laterally against the inside of the neck, the neck would in many instances give the stem suflicient support to avoid breakage.

In the best construction, however, there is a considerable clearance between the post 9 and the neck 8, whereas the crown encircles the neck with a substantially close, free-turning fit.

I claim:

In a watch having a case, a movement, and a stem, the combination of a dust band between the movement and the case, a tube on the dust band extending from the case about the stem, a crown post on the stem inside the tube, and a crown having loose interengagement with the upper portion of the post and encircling the tube.

ARDE BULOVA. 

